1. Field of the Invention
The present invention relates to methods for producing secreted polypeptides. The present invention also relates to isolated nucleotide sequences encoding signal peptides and nucleic acid constructs, vectors, and host cells comprising the signal peptide sequences operably linked to nucleotide sequences encoding polypeptides.
2. Description of the Related Art
The recombinant production of a heterologous protein in a fungal host cell, particularly a filamentous fungal cell such as Aspergillus or a yeast cell such Saccharomyces, may provide for a more desirable vehicle for producing the protein in commercially relevant quantities.
Recombinant production of a heterologous protein is generally accomplished by constructing an expression cassette in which the DNA coding for the protein is placed under the expression control of a promoter, excised from a regulated gene, suitable for the host cell. The expression cassette is introduced into the host cell, usually by plasmid-mediated transformation. Production of the heterologous protein is then achieved by culturing the transformed host cell under inducing conditions necessary for the proper functioning of the promoter contained on the expression cassette.
Improvement of the recombinant production of proteins generally requires the availability of new regulatory sequences which are suitable for controlling the expression of the proteins in a host cell.
U.S. Pat. No. 6,015,703 discloses genetic constructs comprising a promoter, a xylanase secretion signal, and a mature beta-glucosidase coding region. The disclosed constructs, when expressed in recombinant microbes, dramatically increase the amount of beta-glucosidase produced relative to untransformed microbes.
WO 91/17243 discloses an endoglucanase V and the gene thereof from Humicola insolens DSM 1800.
It is an object of the present invention to provide improved methods for producing a polypeptide in a fungal host cell using signal peptide sequences.